<html window-frame="solid"
      window-width="640px"
      window-height="480px" >
    <head>
        <title>Test</title>
        <style>

html { background: gold; }
body { text-align:center; vertical-align:middle; }

        </style>
        <script|module>

class Splash extends Element {

    counter = 16;

    render() {
        return <body>
            Countdown {this.counter}
        </body>;
    }

    componentDidMount() {
       this.timer(1000, ()=>{
          this.componentUpdate({counter: this.counter - 1});
          if( this.counter <= 0 ) {
            if(typeof Window.this.parameters == "function")
                Window.this.parameters();
            Window.this.close();
          }
          else 
            return true; // keep ticking
       }); 
    }
}

document.body.patch(<Splash/>);

        </script>
    </head>
    <body>
    </body>
</html>